Human Genetics

, Volume 119, Issue 1–2, pp 212–219 | Cite as

Y-chromosomes and the extent of patrilineal ancestry in Irish surnames

  • Brian McEvoy
  • Daniel G. BradleyEmail author
Original Investigation


Ireland has one of the oldest systems of patrilineal hereditary surnames in the world. Using the paternal co-inheritance of Y-chromosome DNA and Irish surnames, we examined the extent to which modern surname groups share a common male-line ancestor and the general applicability of Y-chromosomes in uncovering surname origins and histories. DNA samples were collected from 1,125 men, bearing 43 different surnames, and each was genotyped for 17 Y-chromosome short tandem repeat (STR) loci. A highly significant proportion of the observed Y-chromosome diversity was found between surnames demonstrating their demarcation of real and recent patrilineal kinship. On average, a man has a 30-fold increased chance of sharing a 17 STR Y-chromosome haplotype with another man of the same surname but the extent of congruence between the surname and haplotype varies widely between surnames and we attributed this to differences in the number of early founders. Some surnames such as O’Sullivan and Ryan have a single major ancestor, whereas others like Murphy and Kelly have numerous founders probably explaining their high frequency today. Notwithstanding differences in their early origins, all surnames have been extensively affected by later male introgession. None examined showed more than about half of current bearers still descended from one original founder indicating dynamic and continuously evolving kinship groupings. Precisely because of this otherwise cryptic complexity there is a substantial role for the Y-chromosome and a molecular genealogical approach to complement and expand existing sources.


Short Tandem Repeat Short Tandem Repeat Locus Partial Mantel Test Year Before Present Short Tandem Repeat Mutation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We gratefully acknowledge the financial support of Patrick Guinness and Joseph A. Donohoe, through the Trinity Trust, for this research. We thank volunteers for their participation, L.T. Moore for access to pre-published Irish Y-chromosome data as well as K.H. Wolfe, C. Tyler-Smith, M.A. Jobling and T.E. King for helpful discussion.


  1. Bandelt HJ, Forster P, Rohl A (1999) Median-joining networks for inferring intraspecific phylogenies. Mol Biol Evol 16:37–48PubMedGoogle Scholar
  2. Bosch E, Lee AC, Calafell F, Arroyo E, Henneman P et al (2002) High resolution Y chromosome typing: 19 STRs amplified in three multiplex reactions. Forensic Sci Int 125:42–51CrossRefPubMedGoogle Scholar
  3. Byrne FJ (2001) Irish kings and high-kings. Four Courts Press, DublinGoogle Scholar
  4. Cruciani F, Santolamazza P, Shen P, Macaulay V, Moral P et al (2002) A back migration from Asia to sub-Saharan Africa is supported by high-resolution analysis of human Y-chromosome haplotypes. Am J Hum Genet 70:1197–1214CrossRefPubMedGoogle Scholar
  5. Di Rienzo A, Peterson AC, Garza JC, Valdes AM, Slatkin M et al (1994) Mutational processes of simple-sequence repeat loci in human populations. Proc Natl Acad Sci USA 91:3166–3170PubMedCrossRefGoogle Scholar
  6. Excoffier L, Smouse PE, Quattro JM (1992) Analysis of molecular variance inferred from metric distances among DNA haplotypes: application to human mitochondrial DNA restriction data. Genetics 131:479–491PubMedGoogle Scholar
  7. Helgason A, Hrafnkelsson B, Gulcher JR, Ward R, Stefansson K (2003) A population wide coalescent analysis of Icelandic matrilineal and patrilineal genealogies: evidence for a faster evolutionary rate of mtDNA lineages than Y chromosomes. Am J Hum Genet 72:1370–1388CrossRefPubMedGoogle Scholar
  8. Hill EW, Jobling MA, Bradley DG (2000) Y-chromosome variation and Irish origins. Nature 404:351–352CrossRefPubMedGoogle Scholar
  9. Jobling MA (2001) In the name of the father: surnames and genetics. Trends Genet 17:353–355CrossRefPubMedGoogle Scholar
  10. Jobling MA, Tyler-Smith C (2003) The human Y chromosome: an evolutionary marker comes of age. Nat Rev Genet 4:598–612CrossRefPubMedGoogle Scholar
  11. Kim YJ, Paik SG, Ahn GS, Kim W (1999) 49a/TaqI haplotypes according to the surname groups in Korean population. Korean J Genet 21:181–192Google Scholar
  12. MacLysaght E (1985a) Irish families: their names, arms and origins. Irish Academic Press, DublinGoogle Scholar
  13. MacLysaght E (1985b) The surnames of Ireland. Irish Academic Press, DublinGoogle Scholar
  14. Moore LT, McEvoy B, Cape E, Simms K, Bradley DG (2006) A Y-chromosome signature of hegemony in Gaelic Ireland. Am J Hum Genet 78(2): (Epub December 2005)Google Scholar
  15. Morral N, Bertranpetit J, Estivill X, Nunes V, Casals T et al (1994) The origin of the major cystic fibrosis mutation (delta F508) in European populations. Nat Genet 7:169–175CrossRefPubMedGoogle Scholar
  16. Nicholls KW (2003) Gaelic and gaelicized Ireland in the Middle Ages. Lilliput Press, DublinGoogle Scholar
  17. Rolf B, Meyer E, Brinkmann B, de Knijff P (1998) Polymorphism at the tetranucleotide repeat locus DYS389 in 10 populations reveals strong geographic clustering. Eur J Hum Genet 6:583–588CrossRefPubMedGoogle Scholar
  18. Rosenberg MS (2001) PASSAGE. Pattern analysis, spatial statistics, and geographic exegesis, version Department of Biology, Arizona State University, ArizonaGoogle Scholar
  19. Saillard J, Forster P, Lynnerup N, Bandelt HJ, Norby S (2000) mtDNA variation among Greenland Eskimos: the edge of the Beringian expansion. Am J Hum Genet 67:718–726CrossRefPubMedGoogle Scholar
  20. Schneider S, Roessli D, Excoffier L (2000) ARLEQUIN version 2.000: software for population genetic analysis. Genetics and Biometric Laboratory, University of Geneva, SwitzerlandGoogle Scholar
  21. Smouse PE, Long JC, Sokal RR (1986) Multiple regression and correlation extension of the Mantel test of matrix correspondence. Syst Zool 35:627–632CrossRefGoogle Scholar
  22. Sykes B, Irven C (2000) Surnames and the Y chromosome. Am J Hum Genet 66:1417–1419CrossRefPubMedGoogle Scholar
  23. Tremblay M, Vezina H (2000) New estimates of intergenerational time intervals for the calculation of age and origins of mutations. Am J Hum Genet 66:651–658CrossRefPubMedGoogle Scholar
  24. Woulfe P (1923) Sloinnte gaedeal is gall. Gill, DublinGoogle Scholar
  25. Y Chromosome Consortium (2002) A nomenclature system for the tree of human Y-chromosomal binary haplogroups. Genome Res 12:339–348CrossRefGoogle Scholar
  26. Zhivotovsky LA, Underhill PA, Cinnioglu C, Kayser M, Morar B et al (2004) The effective mutation rate at Y chromosome short tandem repeats, with application to human population-divergence time. Am J Hum Genet 74:50–61CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Smurfit Institute of GeneticsTrinity CollegeDublin 2Ireland

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